THE OLIG00H.ETA OF NATAL AND ZULULAND. 445 



number of the seta! glands ; there are four or five of such 

 glands connected with each pair of sexual setae, while there 

 are only two of them in M. colletti and M. gracilis. 



Microchfetus parvus n. sj). PI. XXXII, fig, 12. 



Hab. — Hilton Road, eleven miles N.W. of Pieterraaritzburg, 

 Natal; Dr. M. A — , July 28th, 1905 (one specimen). 



External Characters. — Dimensions : length 54 mm., dia- 

 meter 3-4 mm., number of segments 115. Perhaps the hind 

 end was regenerated. 



Colour, yellowish-grey. Head prolobous. 



Segments 1-3 simple ; the first and second are very short, 

 the third is as long as the first two together. The fourth 

 to the ninth segments are divided into two ringlets, and 

 the furrows of annulation are quite as strongly marked as 

 the intersegmental furrows. The ringlets of segments 4 and 

 5 are of equal length, and as long as the whole third segment. 

 In the case of segments 6-9 the front ringlet bears the setse 

 and the nephridial pores, and is longer than the hind ringlet. 

 In the tenth and following segments biannulation is indistinct 

 or absent. 



Setffi are rather small ; they occur apparently from the third 

 segment. ' Distances : aa somewhat larger than he ; dd equals 

 about half the circumference of the body. 



Nephridial pores are in the lines of setse c. 



The clitellum is indistinct and extends over about ten 

 segments — from the twelfth to the twenty -first. The copula- 

 tory walls are broad longitudinal ridges just above the lines 

 of the nephridial pores. They ai-e distinctly prominent on 

 segments 16 and 17, indistinct on segment 18, and hardly 

 perceivable on segment 15. 



The male pores occur on the copulatory walls in the furrow 

 between segments 16 and 17 (or 15-16?). The sperm-ducts 

 do not enter the body-wall before the furrow between seg- 

 ments 15-16. 



Spermathecal pores are single or double, and occur in the 



VOL. 2, PART 4. 30 



